1. Field of Invention
The present invention relates to a method of fractionation of oil obtained by pyrolysis of lignocellulosic materials, and is particularly related to the fractionation of such oil to recover valuable fractions, including a phenolic fraction. This invention is also concerned with the use of the phenolic fraction obtained from this fractionation to make phenol-formaldehyde resins.
2. The Prior Art
Lignocellulosic wastes such as bark, sawdust, treetops, limbs and the like are pyrolyzed on a commercial scale to obtain a low BTU fuel gas, char for use in making charcoal briquets or activated carbon, and a pyrolytic oil fraction comprising a complex mixture of various chemical compounds presently used as a low cost fuel. Fractionation of the pyrolytic oil yields valuable chemical products, including a phenolic fraction. It has been found that this phenolic fraction can be used as partial or total replacement for pure phenol in making phenol-formaldehyde resins.
Accordingly, it is an object of this invention to provide a method of producing various useful chemicals to replace chemicals currently derived from petroleum.
It is a further object of this invention to derive various useful chemicals from chemical separation of the oily fraction obtained by the pyrolysis of lignocellulosic wastes such as bark, sawdust, treetops, limbs and the like.
It is still another object of this invention to obtain a fraction rich in phenols and polyphenols by chemical fractionation of such pyrolytic oils.
It is also an object of this invention to use the phenolic fraction obtained from fractionation of such pyrolytic oils in making phenol-formaldehyde resins.
The foregoing and other objects of this invention will be more clearly comprehended from the ensuing detailed description of the invention taken in conjunction with the accompanying drawing which is a simplified schematic flow representation of the fractionation method of this invention.